SIGGRAPH 97 Video Formats Color Defined NTSC Y or Luminance channel Black and white video and sync Composed of 30%Red, 59%Green, 11%Blue Color channels (color difference) r-Y = +70% Red -59% Green -11% Blue b-Y = -29% Red -59% Green +89% Blue

NOTES:
All video cameras start out viewing the world as an RGB spectrum. All televisions and video monitors display images as RGB images. Why a then all of this hocus pocus with color difference. The anwser is that inorder to support black and white televisions, when color was first being introduced, the color signal needed to contain a image that could be displayable on an existing black and white set. For this reason RGB was not a suitable answer.

Color difference signals are often referred to by a variety of terms, see the next slide for a description of the differences.